A chemical adsorption method has been well known as a method of forming monomolecular films in solution. In this method, monomolecular films are formed by a dehydrochlorination reaction between the chlorosilyl groups of fluorocarbon-based chemical adsorbents in solution and active hydrogens such as hydroxyl groups, carboxylic acids, amino groups, imino groups or the like on substrate surfaces (for example, EPC-0492545A2/1992, U.S. Pat. No. 4,992,300, 1991).
In this conventional chemical adsorption method, however, it has been difficult to form a highly water- and oil-repelling film (having a contact angle of 130.degree. or higher) with excellent anti-mist, anti-contamination and anti-frost properties on a flat member surface.